Greetings all,

Wondering if I could get some other minds on an issue that I'm experiencing with my 2006 XL883C

Story time! I took the bike for a ride after work a couple days ago up a local canyon here in the salt lake valley. One that I've gone up many times with no issues before in the two years I've owned this bike. As I was starting to reach the top it started bogging pretty bad and felt like it had no acceleration in 3rd, 4th, or 5th. I get to the top, hang out for a bit and let the bike rest, hope back on it fired right up and went back down with no issues. Took the bike to work the next day and everything seemed ok.

I get home and think the carb just needs to be cleaned so I tear it apart yesterday clean the float bowl, jets, float, float needle, primary needle, check to make sure there are no tears in the diaphragm, check the enricher, etc, put it back together and pop it back on.

I also checked the spark plugs they were a tad bit on the lean side but nothing bad kinda of like a whitish brown. I double checked the gap and it was at 30,000ths from what I've read for 883 Sportsters it's supposed to be between 38-42 so I gapped it to 40.

Once everything was back together I fired it up and it was idling perfect, shut it down I walk away for a bit and come back to take it for a spin and when I go to take off and put it under load it died, tried firing it back start idling funky go to take off again it dies. At this point, I notice that it's puttering black puffs of smoke out the exhaust when turning over which normally means it's running way too rich.

I take the plugs out and they are fowled, thinking it's not getting enough spark gapped the plugs back down to 35,000ths cleaned them, checked for spark, tried firing it up again no idling same issue black plugs repeat the process put it back to 30,000ths still nada.

I take the air filter off tried firing it up it starts and idles for a bit, but still black smoke and it's spraying fuel like it's dumping way too much fuel from the carb. If I put the filter back on and it won't even idle.

Reading on some other forums others have said the vacuum petcock can cause dumping issue so I took that apart today and inspected it but there were no tears and only a little bit of crud in it so I cleaned it. Also picked up a carb rebuild kit and threw that on today with no change even with running the vacuum line on and off the carb.

This is a completely stock bike jets are 180 and 42, stock air cleaner, stock exhaust, plugs are back at 30,000ths.

I'm at a complete loss at this point and not sure where to go next, any help would be greatly appreciated.

Sorry for the wall of text.

Cheers

 

Taking a guess I'd check that the fuel float is set correctly.

 

hmmm I'll double check to make sure the float is set correctly and make an update shortly.

 

OK so opened the float bowl and measured the float and it's sitting in spec at 1.1cm between 15 and 20 degrees.

This is what I'm referencing
https://cv-performance.com/harley_float_setting

 

Is the gas fresh? How long was it sitting between the last trouble free ride and when this issue first started?

 

I ride the bike almost everyday during the riding season, and I fill up the tank with premium every tank. I filled up right before the ride up the canyon, I'll swap out the gas in case but hard to believe that's whats causing too much fuel to dump from the carb.

I'm also going to drop the main jet to a 175/170 and see if that helps.

 

Another possibility and often overlooked is a bad/torn petcock diaphragm. If the diaphragm leaks it allows fuel to flow through the vacuum line back into the carb.

Pull the vacuum line off the petcock and see if it's wet inside.

 

Opened up the petcock and diaphragms are good no tears they were a bit cuddy on the inside one but I cleaned it out. The vacuum line is bone dry and the ends aren't stiff or cracked either.

 

Ok so dropped the main jet down to 170 and that didn't help the issue, also completely drained the gas and put fresh 91 as thats the highest I have around me. Plugs are still getting fowled, doesn't want to stay idling/dying under load when I do get is running for a minute, and black puffs of smoke out the exhaust. When I have the air filter off it looks like it dumping a lot of fuel from the carb tot he engine.

I have double checked the vacuum line and it's still bone dry inside.

I am now at a complete loss at this point.

To recap what I've tried:
-New plugs
-New gas
-Cleaned twice and rebuilt the carb
--- new o rings, float needle, accelerator pump diaphragm and o rings, intake manifold seal
-Checked to make sure the float is set correctly (currently sitting at 11mm between 15 and 20 degrees)
-Checked the main diaphragm for tears
-Checked the petcock diaphragm for tears

The idle mixture screw is set 2 turns out
It has new fuel lines
I have a fuel filter between the petcock and the carb

The bike has 9600 miles on it

Damn carbs :'(

 

Yea, it won't be the main jet, that doesn't come into play until you reach about 3/4 throttle.

Since you've have the carb apart, is the needle jet holder still in place? They have a habit of falling out when you remove the needle jet.

Arrow points to the (silver) needle jet holder.